Sylpheed is a simple, lightweight but featureful, and easy-to-use e-mail client (mailer, MUA). Sylpheed runs on Unix-like systems such as Linux, BSD, and Mac OS X. It also supports Windows. Sylpheed uses GTK+ GUI toolkit. The newest version of Sylpheed works with GTK+ 2.4 or later (2.6 or later is recommended). Sylpheed is a free software distributed under the GNU GPL (the library part is GNU LGPL). You can freely use, modify and redistribute it under the license.
Sylpheed has the following features:
* Simple, beautiful, and well-polished user interface
* Comfortable operationality which is built in detail
* Well-organized, easy-to-understand configuration
* Lightweight operation
* High reliability
* Internationalization and Multilingualization support
* High-level Japanese processing
* Various protocols support
* Security features (GnuPG, SSL/TLSv1)
* Powerful filtering and search
* Junk mail control
* Flexible cooperation with external commands
* The 'To' column was added to the summary view.
* In Sent, Draft, and Queue folders, the 'To' column is displayed by default.
* The display column setting of send folders became independent from normal folders.
* The ascii-armored PGP encryption was fixed.
* The combined method is used now when both PGP encryption and PGP signing are specified.
* The PGP passphrase dialog was disabled on filtering and query search.
* The new message notify will be blocked when a new message is read on receiving.
* 'LIST "" "*"' command is used instead of 'LIST "" "%"' to obtain folder list from IMAP4 server.
* The bug that noinferior and noselect flags were ignored until rebuilding folder tree when a new folder was created on IMAP4 server was fixed.
* If attached files become nonexistent on sending, error dialog will be displayed and the sending will abort.